A B C D E F G I L M N O P Q R S T V Z
General term for mixtures of gases (e.g., air) that contain suspended solid or liquid particles (so-called particulate matter) which are approximately 1 nm to 10 μm in diameter. Sea salt aerosols, for example, are formed as sea water droplets that are dispersed into the atmosphere by wind evaporate to leave sea salt particles.
atomic force microscopy. The AFM tip scans the sample line for line. Due to repulsion between needle and sample, a movement of the tip is detected. A three dimensional image can be simulated.
Accumulations of weakly bound particles or aggregates or of compounds of these, whose resulting surfaces are similar to the sum of surfaces of the individual components. Agglomerates are held together by weak forces, for example Van der Waals forces or simple physical hooks. Agglomerates are referred to as secondary particles, while the unbound particles are known as primary particles.
See also ISO/TS 27687:2008 (E),
International Organization for Standardization
Solidly bound or molten particles, whose resulting surface may be much smaller than the sum of the calculated surfaces of the individual components. Aggregates are held together by strong forces such as covalent bonds or forces caused by sintering or complex physical hooking. Aggregates, just as agglomerates, are referred to as secondary particles.
See also ISO/TS 27687:2008 (E),
International Organization for Standardization
Description of a method (Brunauer-Emmett-Teller) for the analysis technique of sizing surfaces by means of gas adsorption.
Literal meaning „from bottom to top“. Production process starting from small units (from atoms, for example, in nanotechology).
or Buckyball, these are other terms for the carbon compounds described under fullerenes . They are derived from the name of Buckminster Fuller, the ”inventor“ of the fullerene structures.
The property of nanomaterials to penetrate cell walls or membranes due to their small size is referred to as cell penetration capacity.
is a covering that is applied as a thin film to the surface of an object, e.g. nanoparticles. Coatings are applied to improve surface properties of the nanoparticles, such as solubility, adhesion, wetability, and corrosion resistance, and to reduce dissolution of ions. Frequently used coatings in nanotechnology include polymers, lipids (medical applications) or metals (catalysts).
Very small solid particles (typically smaller than 10 µm) suspended in a solvent. Compared with solids in suspensions, solids in a colloid do not precipitate, i.e. do not sink to the bottom of a vessel. In liquids, colloids are recognized by clouding and/or the so-called Tyndall effect.
describes the regular arrangement of atoms or molecules in a crystal lattice. Different lattice structures of the same material (e.g. titanium dioxide) give nanoparticles different chemical and physical properties (e.g. photocatalytic activity).
to deposit, marks the deposit of solid, liquid and gaseous particles in the organism
Physical process leading to the mixing of different gaseous, liquid or solid substances theat are in contact with each other.
Materials that are impurified during production with small parts of another material (intentional impurification) are referred to as doped materials. Such traces of other elements can decisively affect the properties of a material, as, for example, is the case with different types of steel. In nanoparticles, individual atoms can be replaced by other atoms.
derived from the Greek terms epi = upon, among; demos = people, district; logos = study. "The study of what is upon the people", Scientific studies are dealing with the reasons, impacts and extension of health related substances in populations. Epidemiological studies show impacts of toxic substances on the human population, often unintended by incident.
Atoms or molecules that contain one or several unpaired electrons and, in that sense, are „free“. Correspondingly, any free radical has an electron that stands alone. Many free radicals are highly reactive, meaning that they have a strong tendency to arrange in pairs and, thus, escape the instable unpaired condition. For pairing, free radicals randomly receive electrons from a suitable donor or donate electrons to an appropriate aceptor which converts into secondary free radicals. Such chain reactions may cause biological damage.
Genotoxic effects are damages to the genetic material of organisms (DNA). They can lead to mutations or increase the error rate in the doubling of DNA at each cell division. Genotoxicity is therefore not necessarily associated with mutagenicity.
means the simulation of biological and biochemical processes using computer programs.
“In the test tube”, from the Latin vitrum – glass, referring to reactions outside the organism, sometimes under participation of autologous physiological conditions.
from the Latin vivus – alive, characterising reactions or processes that take place in the living organism under physiological conditions.
Lethal dose. Concentration of a substance that leads to death of 50% of the organisms exposed to it.
Lowest observed effect level.
Is the simulation of different processes (biochemical processes in cells, material flows of nanoparticles in ecosystems) using especially developed computer programs. By changing relevant parameters of a process, modelling allows predictions and saves laborious experiments.
describes the capacity of certain chemicals or high energy radiation to cause changes in the genetic material (DNA), known as mutations.
or nano-scale, size range from approximately 1 nm to 100 nm.
Nano-object with all three external dimensions in the nanoscale.
See also ISO/TS 27687:2008 (E),
International Organization for Standardization
no observed (adverse) effect level.
latin noxa – damage, every harmful effect on man and/or environment.
results from an imbalance between the intracellular production of free radicals and the cellular defense mechanisms. The balance between oxidants and antioxidants may be disturbed by the increase in free radicals or the reduction of antioxidant substances. Oxidative stress may cause destructive biochemical reactions.
Predicted Environmental Concentration, is a theoretical value giving an indication of the expected concentration of a material (e.g. nanoparticles) in the environment (exposure assessment). The calculation takes into account the amount initially present (or added to) the environment, its distribution in the different environmental compartments, and the probable rates of environmental degradation and removal, either forced or natural.
Modified after http://msds.chem.ox.ac.uk/glossary/pec.html
In biology and environmental chemistry, the term “persistence” denotes the property of substances to persist in the environment over long periods of time while remaining unchanged by physical, chemical or biological processes.
predicted no effect concentration, predicted concentration of a hazardous substance in the environment which shows no impact on the environment (effect assessment). If this concentration is thus below the PNEC, it should not have any negative effects. PNECs find application especially with PECs in the risk quotient in environmental risk assessment.
also IEP or pI, is an important parameter for assessing the behaviour of nanoparticles in aqueous surroundings. The IEP is the pH of an aqueous suspension, where the positive and negative charges on the particle surfaces are balanced. The IEP for each particle type is individually different and an important material parameter to assess the stability of particles in suspension.
nanoparticles, which can affiliate to a bigger linked system (agglomerate, aggregate).
crystaline nanoparticle that exhibits size-dependent properties due to quantum confinement effects on the electronic states.
See also ISO/TS 27687:2008 (E),
International Organization for Standardization
Registration, Evaluation, Authorization of Chemicals. REACH is the novel EC regulation no. 1907/2006 that has been in force since June 1, 2007. For further information, see http://echa.europa.eu/reach_en.asp
reactive oxygen species, the organism considering harmful forms of oxygen, which result from oxidative stress.
superparamagnetic iron oxide nanoparticles.
Solid particles suspended in a liquid, i.e. a more or less thick sludge or slurry. Normally, the solid particles deposit on the bottom if one allows the suspension to rest for a while in the vessel.
is the electric charge present at the interface of the nanoparticle surface with a polar fluid such as water. The water contains positive and negative ions, which interact with the particle surface. If the number of adsorbed e.g. positive ions exceeds the number of negative ions, surface charge would be positive. Since direct measurement of the surface charge of particles measured is difficult, the zeta potential is calculated as a proxy for the surface charge.
Transmission electron microscopy. Method for examining the smallest materials by radiographing the sample using electron rays. The wavelength is about 5 nm depending on the configuration of the equipment. The sample to be examined can be enlarged by one million times.
Literal meaning „from top to bottom“. Production process starting from large units and proceeding with comminution (for example, cutting or grinding).
from the Greek words τοξικός - toxicos "poisonous" and logos, study of the adverse effects of poison
The term “toxicity” denotes the poisonousness of a substance, i.e. its property of developing undesired effects and of impairing functions in cells or living organisms. Effects caused by toxicity may even cause death of the affected organism.
From the Latin vesicula – small bubble . Round or oval compartments that are approximately 100 nm in diameter. Vesicles are located in the cells and are surrounded by separating layers (membranes).
also ζ-potential, is the electrical potential at the contact layer of a moving particle with an aqueous solution (suspension). Thus, within the same suspensions, it is a relative measure of the surface potential and thus the charge of the particle. For the measurement of the zeta potential, charged particles are moved through an applied electric field. The resulting speed is then a measure of the zeta potential.